Electric railway signaling system.



No. 692,9I6. Patented Feb. n, I902.

' w. w. SALMON.

ELECTRIC RAILWAY SIGNALING SYSTEM.

(Application filed July 21, 1900.)

MS ATTOR N EYE THE uonms PETERS w. PHOTO-LUNG. WASHINGTUN. n. c.

UNITED STATES PATENT O FICE.

WILMER W. SALMON, OF CHICAGO, ILLINOIS.

ELECTRIC RAILWAY SIGNALING SYSTEM.

SPECIFICATION formingpart of Letters Patent No. 692,916, dated February 11, 1902.

Application filed July 21, 1900. S r l N 2 ,359- (No l- T0 all. whom it may concern.-

Be it known that I, WILMER W. SALMON, a citizen of the United States, and a resident of Chicago, Cook county, and State of Illinois, have invented certain new and useful Improvements in Electric Railway Signaling Systems, of which the following is a specification.

This invention relates to electric railway signaling systems, and seeks, among other things, to provide an efficient and economical arrangement of circuits and also to arrange the signal-circuitin such a way that it may be energized and denergized by excluding and including resistance. Thus instead of maintaining an actual physical break in the circuit to deenergize it I deenergize it by including in the circuit a suitable resistance which enables the battery to be keptin a state of diminished activity, so that the current on the line is too weak to operate the signal device. In case the signal-circuit is to be normally deenergized the resistance would be normally included in the circuit. If desired, I may employ a resistance to be included in the circuit at every point where the circuit would otherwise be broken, and this would at least be generally done at all points where a cir cuit-controller is employed to keep the circuit deenergized for prolongedperiods.

Heretofore in the practical art so far as known an actual physical prolonged break has been relied upon for denergizing the sig nal-circuit. I have in place of this arrangement provided a signal-circuit wherein the operation of the signal-circuit is made to depend upon the inclusion or exclusion of a resistance-coil. One of the advantages of this arrangement is-that the life of the batteries is prolonged by keeping them always in closed circuit. Again, the sparking at the contactpoints is prevented.

In the drawings, Figure 1 shows a diagram embodying the invention as applied to several blocks of a railway. Figs. 2 and 3 show modified arrangements of circuits embodying the invention.

Referring now to Fig. 1, 1, 2, 3, 4, and 5 are insulated subsections of a railway-track over which traific will be supposed to travel in the direction of the arrow. The signals 6 and 7 are arranged to stand normally at dancircuits.

ger, the signal 6 guarding the block composed of the subsections 2 and 3 and the signal 7 guarding the block composed of the subsections 4 and 5. The rails of the various subsections are included in rail-circuits which control the signal-circuits.

8, 1O, 13, and 15 are the magnets of the rail- 9, 11, 14, and 16 are the batteries of these respective rail-circuits. The railcircuit of subsection 2 contains the circuitcontroller 12, operated by the magnet 13, and the rail-circuit of subsection 4 contains a circuit-controller 17, operated by the magnet 34, which is included in the circuit of subsection 5. The signal-circuit of signal 6 includes the battery 18, wire 19, circuit-controller 20, hav ing the front and back contact-points 22 and 21, wire 23, and circuit-controller 24, having front and back contacts 26 and 25. The signal-circuit has a suitable resistance, such as a resistance-coil 27, connected to the wire 23 and to the front contact 26. It also has a suitable resistance, such as a resistance-coil 28, connected to the wire 19 and to the back contact 21. The signal-circuit 29 of the signal7 is similarly arranged, having the resistancecoils 30 and 31 and circuit-controllers 32 and 33. The circuit-controllers 20, 24,32, and 33 are normally heldagainst their front contacts, as shown, so that normally the resistance-coils 27 and 31 are included in the circuits of the signal-batteries, and these resistances are sufficient to normally maintain the circuit in deenergized condition-that' is to say, too weak to operate the signals-so that thus the signals stand normally at danger.

In the operation of the system a train on subsection 1 shunts the magnet 8, thereby moving the circuit-controller 24 from its front contact 26 upon its back contact 25, so as to exclude the resistance 27 from the signal-circuit. The signal-circuit thereupon becomes energized, so as to put the signal 6 to safety in advance of the train. When the train reaches subsection 2, the magnet 10 is shunted and the circuit-controller 20 moves from its front contact 22 upon its back contact 21, thereby including the resistance 28 in the signal-circuit and denergizing the signal-circuit, so that the signal 6 returns to danger. The train operates the signal-circuit of signal 7 in the same way.

Of course as long as a train remains in the block 2 it will keep the signal-circuit denergized and hold the signal 6 at danger, so that as long as the first train remains in block 2 a following train will not be able to put the signal 6 to clear, although it may cut outthe resistance 27.

If desired, the signals may be arranged to stand normally at safety, with the signalcircuits normally energized. In this case it would not be necessary for a train to operate the signal-circuit in advance of the signal, so that the circuit-controllers 24 and 33, with their contacts and associated resistance-coils, would in such case be omitted.

Again, when employing normally-deem?!- gized sign al-circuits with the signals normally at danger, as shown in the accompanying drawings, I may in some cases omit the resistance-coils 28 and 30. In such case there would be an actual and physical break at the circuit-controllers 20 and 32 during such short periods when a train was actually in the respective blocks guarded by the signals 6 and 7.

In Fig. 2 the resistance-coil 27 is connected with the circuit in the same way as is shown in Fig. 1. Instead, however, of employing the resistance-coil 28, as arranged in Fig. 1, I show a resistance-coil 37, connected at one end to the wire 19 between the battery and the contact 22 and connected at its other end to the wire 23 at the side of the signal opposite to the circuit-controller 20. Thus the signal 6 and circuit-controller 20 are in a branch parallel with but of lower resistance than the branch containing the resistance 37. In the operation of this arrangement the circuitcontroller 24 operates with respect to its contact and the resistance 37 in the same way as is shown in Fig. 1. When, however, the train denergizes the magnet 10, the circuit through controller 20 is broken, leaving the high-resistance branch through the resistance 37 as the only path for the current, and thus deenergizing the signal-circuit.

In Fig. 3 instead of the resistance-coil 27 I show a resistance-coil 38 in a branch arranged in parallel with the circuit-controller 24 and its contact 25. The branch containing the resistance 38 also contains a circuitcontroller 39 and contact 40, which are held normally closed by the magnet 8. Instead, also, of the resistance 28 and contact2l I show a resistance-coil 41, connected in a branch arranged in parallel with the signal 6 and circuit-controller 20. The branch containing the resistance 41 also includes the circuit-controller 42 and the contact 43, held normally open by the magnet 10. In this arrangement the signal is normally at danger and the circuit is normally denergized, because the branch through the circuit-controller 24 is open, and the resistance 38 is included in the circuit. In the operation of this arrangement when the magnet 8 is denergized the branch through the circuit-controller 24 is closed and the branch through the resistance 38 is broken by the movement of the circuit-controller 39 from its contact 40, thus energizing the circuitand putting the signal to safety. When the magnet 10 is deenergized, the branch containing the circuit-controller 2O isbroken and the branch containing the resistance 41 is closed, thereby including the resistance 41 in the circuit and deenergizing the circuit to put the signal to danger.

In employing the words signal-circuit herein I do not limit myself to circuits which necessarily actually include the signal instrument or motor for actuating the signal disk or semaphore. The signal-circuit instead of including the signal instrument or. signalmotor may include any translating device by which the movement of the signal is controlled. This translating device may control the signal instrument or signal-motor through the intermediation of other circuits or connections.

What I claim as new, and desire to secure by Letters Patent, is-

1. In an electric railway signaling system, the combination of a signal-circuit having a resistance-coil and a circuit-controller, the circuit-controller operating to exclude and include the resistance-coil to energize and deenergize the signal-circuit and thereby operate the signal, and means controlled by a train for operating the circuit-controller.

2. In an electric railway signaling system, the combination of a normally denergized circuit having a resistance-coil and a circuitcontroller, the circuit-controller operating to exclude and include the resistance-coil to energize and deenergize the signal-circuit and thereby operate the signal, and means controlled by a train for operating the circuitcontroller.

3. In an electric railway signalingsystem,

the combination of a signal-circuit having a resistance-coil and a circuit-controller, the circuit-controller operating to exclude and in clude the resistance-coil to energize and deenergize the signal-circuit, and thereby oper ate the signal, and a rail-circuit controlled by a train for operating the circuit-controller.

4. In an electric signaling system, the combination of a normally deenergized signalcircuit having a resistance-coil and a circuit controller, the circuit-controller operating to exclude and include the resistance-coil to energize and deenergize the signal-circuit and thereby operate the signal, and a rail-circuit controlled bya train for operating the circuit controller.

5. Inan electric railway signaling system, the combination of a normally denergized signal-circuit normally including a resistance-coil and a circuit-controller, the circuitcontroller operating to exclude and include the resistance-coil to energize and deenergize the signal-circuit and thereby operate the signal, means controlled by a train in the rear of the signal for operating said circuit-com troller to exclude said resistance-coil from the signal-circuit, whereby the train may put the signal to safety in advance thereof, a second resistance-coil normally excluded from the circuit, and a second circuit-controller arranged to' include and exclude said second resistance-coil from the circuit, and means controlled by a train for including the second resistance-coil in the signal-circuit to denergize the signal-circuit and put the'signal to danger in the rear of the train.

6. In an electric railway signaling system, the combination of a normally deenergized signal-circuit normally including a resistance-coil and a circuit-controller, the circuitcontroller operating to exclude and include the resistance-coil to energize and denergize the signal-circuit and thereby operate the signal, and a rail-circuit controlled by a train in the rear of the signal for operating said circuit-controller to exclude the resist- 2o ance-coil from the signal-circuit, whereby a train may, put the signal to safety in advance thereof, a second resistance-coil normally 6X-' 

